//  ImageScrubberViewController.m

#import "ImageScrubberViewController.h"

#define EASE_SPEED 0.95
#define MAX_VELOCITY 6.0
#define DRAG_SCALE_FACTOR 200.0
#define VEL_SCALE_FACTOR 150.0
#define DEFAULT_PRODUCT_KEY @"Ironman_camera_move_v5"
#define IMAGE_ASSET_PATH @"Assets/Images/Product_Overview/"

@implementation ImageScrubberViewController
@synthesize productImage;

- (id)initWithProductKey:(NSString *)productKeyStr
{
    NSLog( @"ImageScrubberViewController::initWithProductKey" );

    self = [super initWithNibName:@"ImageScrubberViewController" bundle:nil];

    if (self)
    {
        productKey = [productKeyStr retain];
        numImages = 100;
        currentImage = 0;
        xVel = 0;
    }

    return self;
}

- (id)init
{
    return [self initWithProductKey:DEFAULT_PRODUCT_KEY];
}

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    return [self initWithProductKey:DEFAULT_PRODUCT_KEY];
}

- (IBAction)handlePanGesture:(UIPanGestureRecognizer *)sender
{
    if ( sender.state == UIGestureRecognizerStateBegan )
    {
        touchDown = YES;
    }
    else if ( sender.state == UIGestureRecognizerStateChanged )
    {
        CGPoint vel = [sender velocityInView:sender.view.superview];

        // reduce the dragging impact
        float scaledVel = -vel.x/DRAG_SCALE_FACTOR;
        currentImage += (int)roundf(scaledVel);
    }
    else if (sender.state == UIGestureRecognizerStateEnded )
    {
        CGPoint vel = [sender velocityInView:sender.view.superview];

        xVel = -vel.x/VEL_SCALE_FACTOR;
        xVel = fmax( -MAX_VELOCITY, fminf( MAX_VELOCITY, xVel ) );

        touchDown = NO;
    }
}

- (void)updateFrame:(id)data
{
    if ( touchDown == NO )
    {
        if ( xVel < 0 )
            xVel+=0.1;
        else if ( xVel > 0 )
            xVel-=0.1;

        currentImage += (int)roundf(xVel);
    }

    // wrap image sequence
    if ( currentImage < 0 )
    {
        currentImage = [rotationImages count]-1 + currentImage;
    }

    if ( currentImage > [rotationImages count]-1 )
    {
        currentImage = currentImage - [rotationImages count]-1;
    }

    if ( currentImage < 0 ) currentImage = [rotationImages count]-1;
    if ( currentImage > [rotationImages count]-1 ) currentImage = 0;

    [productImage setImage:(UIImage *)[rotationImages objectAtIndex:currentImage]];
}

- (void)viewDidLoad
{
    NSLog( @"ImageScrubberViewConroller::viewDidLoad" );

    // load all images
    rotationImages = [[NSMutableArray alloc] init];

    for ( int i=0; i<numImages; i++ )
    {
        [rotationImages addObject:[UIImage imageNamed:[NSString stringWithFormat:@"%@%@_000%i.png", IMAGE_ASSET_PATH, productKey, i]]];
    }

    // pan gesture
    UITapGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc]
                                          initWithTarget:self action:@selector(handlePanGesture:)];

    [self.view addGestureRecognizer:panGesture];
    [panGesture release];

    [productImage setImage:(UIImage *)[rotationImages objectAtIndex:0]];

    // sync to frame redraws
    CADisplayLink *frameLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(updateFrame:)];

    frameLink.frameInterval = 1;
    [frameLink addToRunLoop:[NSRunLoop mainRunLoop] forMode:NSDefaultRunLoopMode];

    touchDown = NO;
}

- (void)viewDidUnload
{
    NSLog( @"ImageScrubberViewConroller::viewDidUnload" );

    CADisplayLink *frameLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(updateFrame:)];
    [frameLink removeFromRunLoop:[NSRunLoop mainRunLoop] forMode:NSDefaultRunLoopMode];

    [rotationImages release];
    rotationImages = nil;

    [productImage release];
    productImage = nil;

    [productKey release];
    productKey = nil;

    [productImage release];
    productImage = nil;

    [super viewDidUnload];
}

- (void)dealloc
{
    NSLog( @"ImageScrubberViewConroller::dealloc" );

    [rotationImages release];
    [productImage release];
    [productKey release];

    [super dealloc];
}

@end